JLA (1996) #92
"Extinction Part 2 the Lesson" is written by Dennis O'Neil and drawn by Tan Eng Huat. The alien visitor Pe-Pey has come from another galaxy to observe Earth and question why the silver-masked monkeys he and his people thought would become the predominant species have now been wiped out by over-development of the Amazon jungle. Unfortunately, the JLA don't have much of an answer for him and after witnessing the violent death of the last silver-masked monkey, the alien takes on the frightening shape of a giant ape.
Reason wins out for the moment, however, as Pe-Pey's curiosity leads him to forgo jumping to conclusions and to learn more about humans. Acting as humanity's ambassadors, the JLA agree to escort Pe-Pey around the globe showing him both the best and worst of homo sapiens behavior. It's a big risk as the heroes are unsure what the alien's reaction will be once he realizes how self-destructive the human race can be. Sure enough, Pe-Pey finally announces he's seen enough and he's ready to help mankind if it is truly bent on destroying itself.